Changes in Functionality of Tenebrio molitor Larvae Fermented by Cordyceps militaris Mycelia

The Food and Agriculture Organization (FAO) has been estimating the potential of insects as human food since 2010, and for this reason, Tenebrio molitor larvae, also called mealworms, have been explored as an alternative protein source for various foods. In this study, in order to increase nutrient contents and improve preference as an alternative protein source, we fermented the T. molitor larvae by Cordyceps militaris mycelia. T. molitor larvae were prepared at optimal conditions for fermentation and fermented with C. militaris mycelia, and we analyzed T. molitor larvae change in functionality with proximate composition, β-glucan, cordycepin, adenosine, and free amino acids content. T. molitor larvae fermented by C. militaris mycelia showed higher total protein, total fiber, and β-glucan content than the unfermented larvae. In addition, the highest cordycepin content (13.75 mg/g) was observed in shaded dried T. molitor larvae fermented by C. militaris mycelia. Additionally, the isolated cordycepin from fermented T. molitor larvae showed similar cytotoxicity as standard cordycepin when treated with PC-9 cells. Therefore, we report that the optimized methods of T. molitor larvae fermented by C. militaris mycelia increase total protein, total fiber, β-glucan and produce the amount of cordycepin content, which can be contributed to healthy food and increase T. molitor larvae utilization.